Steering device

Abstract

A steering device (100) comprises: a fixed member (120); a movable member (130) movable relative to the fixed member (120); an upper guide mechanism (140) and a lateral guide member (160) that guide movement of the movable member (130); a movement device (125) for moving the movable member (130); and a movement control device (190) that controls the movement device (125). The movement control device (190) comprises: a reference position determination unit (191) that determines a reference position for arranging the movable member (130); an addition unit (192) that, when advancing the movable member (130), derives an arrangement position by adding an addition value different from that when advancing a previous time to the reference position; and an arrangement control unit (193) that controls the movement device (125) so that the movable member (130) is positioned at the arrangement position.

Description

[Technical Field]

[0001] The present invention relates to a steering device capable of moving an operating member such as a steering wheel operated by a driver to steer a vehicle. [Background technology]

[0002] Conventionally, there are steering devices that change the position of an operating member depending on the driver, and steering devices that store the operating member in the dashboard during automatic driving and place the operating member in a position where the driver can operate it during manual driving.

[0003] For example, Patent Document 1 discloses a steering device in which a movable member to which an operating member is rotatably attached is held slidably relative to a fixed member fixed to the vehicle, and the movable member is moved between an operating position where the driver can operate the operating member and a position in front of the vehicle where operation is no longer necessary due to automatic driving. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Patent Publication No. 2021-109611 Summary of the Invention [Problem to be solved by the invention]

[0005] However, the inventors discovered that repeated application of vibrations of the operating member due to the shaking of the vehicle while in motion, or loads applied to the operating member by the driver when driving manually, to the slide mechanism that slides the movable member causes wear in certain parts of the slide mechanism, resulting in rattles in the operating member and rattles when sliding.

[0006] The present invention is based on the findings of the inventors, and aims to suppress the occurrence of rattle due to deterioration over time in a steering device in which the position of an operating member can be changed. [Means for solving the problem]

[0007] In order to achieve the above-mentioned object, one aspect of the present invention is a steering device used for steering a vehicle, comprising: a fixed member fixed to the vehicle; a movable member rotatably supporting an operating member and movable relative to the fixed member; a guide mechanism for guiding the movement of the movable member relative to the fixed member; a moving device for moving the movable member relative to the fixed member; and a moving control device for controlling the moving device, wherein the moving control device comprises: a reference position determination unit for determining a reference position for positioning the movable member; an addition unit for, when advancing the movable member, adding an additional value different from the previous time the movable member was advanced to the reference position within a range from a predetermined lower limit distance to a predetermined upper limit distance to derive a position; and a positioning control unit for controlling the moving device so that the movable member is positioned at the position derived by the addition unit. [Effects of the Invention]

[0008] According to the present invention, by changing the position of the load applied to the guide mechanism to level out wear and suppress localized wear, it is possible to suppress rattling of the operating member attached to the movable member and rattling when the movable member moves. [Brief explanation of the drawings]

[0009] [Figure 1] 1 is a schematic diagram showing a configuration of a steering system according to an embodiment; [Figure 2] 1 is a perspective view showing the appearance of a steering device according to an embodiment; [Figure 3] FIG. 4 is an exploded perspective view of the lateral guide mechanism. [Figure 4] FIG. 2 is an exploded perspective view showing the upper guide mechanism. [Figure 5] FIG. 2 is a block diagram showing the functional configuration of a mobile control device. [Figure 6] FIG. 10 is a diagram illustrating the relationship between a reference position, an additional value, a placement position, a lower limit value, and an upper limit value. [Figure 7] FIG. 10 is a block diagram showing another example of the functional configuration of the movement control device. DETAILED DESCRIPTION OF THE INVENTION

[0010] Hereinafter, an embodiment of a steering device according to the present invention will be described with reference to the drawings. Note that the following embodiment is an example for explaining the present invention and is not intended to limit the present invention. For example, the shapes, structures, materials, components, relative positional relationships, connection states, numerical values, mathematical formulas, the content of each step in a method, and the order of each step shown in the following embodiment are examples and may include content not described below. Furthermore, while geometric expressions such as parallel and orthogonal may be used, these expressions do not indicate mathematical precision and include substantially allowable errors, deviations, etc. Furthermore, expressions such as simultaneous and identical also include substantially allowable ranges.

[0011] The drawings are schematic diagrams in which emphasis, omission, or adjustment of proportions is appropriately made for the purpose of explaining the present invention, and differ from the actual shapes, positional relationships, and proportions. The X-axis, Y-axis, and Z-axis shown in the drawings represent Cartesian coordinates arbitrarily set for the purpose of explaining the drawings. In other words, the Z-axis is not necessarily an axis along the vertical direction, and the X-axis and Y-axis are not necessarily located within a horizontal plane.

[0012] In addition, in the following, multiple inventions may be collectively described as one embodiment, and some of the contents described below may be described as optional components related to the present invention.

[0013] 1 is a schematic diagram showing an outline of the configuration of a steering system 200 according to an embodiment. The steering system 200 according to this embodiment is a device mounted on a vehicle such as a passenger car, bus, truck, construction machine, or agricultural machine that can switch between a manual driving mode and an automatic driving mode.

[0014] 1, steering system 200 includes steering device 100 having an operation member 210 operated by the driver, and a steering mechanism unit 230 that steers steerable wheels 220. Steering system 200 is a system that, in a manual driving mode, for example, reads the rotation angle of operation member 210 with a sensor or the like, and steers steerable wheels 220 by causing rack shaft 231 to reciprocate left and right based on a signal from the sensor or the like. Such a system is called, for example, a steer-by-wire (SBW) system.

[0015] In steering mechanism 230, movement of rack shaft 231 in the width direction of the vehicle (left and right direction in FIG. 1 ) causes steerable wheels 220 connected to rack shaft 231 via tie rod 232 to turn. Specifically, in manual driving mode, steering actuator 233 operates based on a signal indicating the rotation angle of operating member 210, etc., transmitted from steering device 100. This causes rack shaft 231 to move in the width direction of the vehicle, and steers steerable wheels 220. In other words, steerable wheels 220 are turned in accordance with the operation of operating member 210. In autonomous driving mode, steering actuator 233 operates based on a signal, etc., transmitted from an ECU (Electronic Control Unit) for autonomous driving provided in the vehicle, and thereby steers steerable wheels 220 regardless of the operation of operating member 210. 1 illustrates a configuration in which the driving force of steering actuator 233 is transmitted to rack shaft 231 using a belt, but there are no particular limitations on the method of transmitting the driving force of steering actuator 233 to rack shaft 231. For example, the driving force of steering actuator 233 may be transmitted to rack shaft 231 via a pinion gear fixed to the rotation shaft of steering actuator 233.

[0016] Fig. 2 is a perspective view showing the appearance of the steering device 100 according to the embodiment. Fig. 2 shows the steering device 100 when the movable member 130 has moved relative to the fixed member 120 and is in a position where it is advanced toward the driver.

[0017] The steering device 100 according to this embodiment includes an input shaft 110, a fixed member 120, a movable member 130, an upper guide mechanism 140 which is one of the guide mechanisms, a lateral guide mechanism 160 which is another of the guide mechanisms, a moving device 125, and a movement control device 190 which will be described later.

[0018] The input shaft 110 is a rod-shaped member to which an operating member 210, which is operated by the driver to steer the vehicle, is attached at its tip, and is rotatably supported by the movable member 130. A reaction force generator, a rotation angle sensor, etc. are attached to the input shaft 110, and a reaction force is applied to the operating member 210 when the driver operates the operating member 210. In addition, the rotation angle sensor outputs a signal for synchronizing the rotation position of the operating member 210 with the steering angle of the steered wheels 220.

[0019] The fixed member 120 is a member that is fixedly attached to a reinforcement, which is one of the structural members of the vehicle body. The manner in which the fixed member 120 is attached to the vehicle body is not limited, but in this embodiment, the fixed member 120 is attached in a suspended state to a reinforcement that is stretched across the width direction of the vehicle body. The cross-sectional shape of the fixed member 120 perpendicular to the movement direction of the movable member 130 relative to the fixed member 120 (the Y-axis direction in the figure) is an L-shape rotated 90 degrees to the right, and the fixed member 120 includes a plate-like fixed top panel portion 121 and a fixed wall portion 122 that extends downward on one side (the X-side in the figure) of the fixed top panel portion 121 in the width direction (the X-axis direction in the figure).

[0020] A moving device 125 for moving the movable member 130 is attached below the fixed member 120 (on the Z-side in the drawing). The type of moving device 125 is not particularly limited, but in this embodiment, it includes a feed screw 127 rotatably attached to the fixed member 120 via a fixed bracket 126 so as to extend in the movement direction of the movable member 130 (the Y-axis direction in the drawing), a movable nut 138 that meshes with the feed screw 127 and reciprocates in the movement direction of the movable member 130 as the feed screw 127 rotates, and a rotation drive device 128 that includes a motor (not shown) that rotates the feed screw 127. The type of motor is not limited, but if the motor is a servo motor, for example, the moving device 125 may include a servo amplifier or the like.

[0021] The movable member 130 is attached to the fixed member 120 so as to be reciprocable between an advanced position and a retracted position by guide mechanisms, namely, an upper guide mechanism 140, a lateral guide mechanism 160, and a moving device 125. An input shaft 110 that holds an operating member 210 is rotatably attached to the movable member 130. In this embodiment, the cross-sectional shape of the movable member 130 perpendicular to the direction of movement (the Y-axis direction in the figure) is an L-shape rotated 90 degrees to the right, and the movable member 130 includes a plate-like movable top panel 131 and a movable wall portion 132 that extends downward from one side (the X-side in the figure) of the movable top panel 131 in the width direction (the X-axis direction in the figure). The movable wall portion 132 is thicker than the fixed wall portion 122 in the width direction and is provided with a through-hole 135 therein through which a harness or the like connected to an operating switch or the like can be inserted.

[0022] Fig. 3 is an exploded perspective view of the lateral guide mechanism 160. Fig. 4 is an exploded perspective view of the upper guide mechanism 140. The lateral guide mechanism 160 and the upper guide mechanism 140 function as guide mechanisms that guide the movement of the movable member 130 relative to the fixed member 120.

[0023] As shown in FIG. 3 , the side-side guide mechanism 160 includes a side-side fixed rail 161, a side-side movable rail 162 slidably attached to the side-side fixed rail 161, and a plurality of side-side rolling element rows 163. The side-side rolling element rows 163 are composed of a plurality of rolling elements aligned in the direction of movement of the side-side movable rail 162 relative to the side-side fixed rail 161. The rolling elements are disposed between a side-side fixed track surface 164 of the side-side fixed rail 161 and a side-side movable track surface 165 of the side-side movable rail 162. In this embodiment, the side-side fixed rail 161 has two side-side fixed track surfaces 164, and the side-side movable rail 162 has two side-side movable track surfaces 165. The side-side fixed rail 161 and the side-side movable rail 162 are combined so that each of the two side-side movable track surfaces 165 faces a side-side fixed track surface 164. That is, the lateral guide mechanism 160 has two sets of opposing lateral fixed raceway surfaces 164 and lateral movable raceway surfaces 165. In each of the two sets of lateral fixed raceway surfaces 164 and lateral movable raceway surfaces 165, a lateral rolling element row 163 is disposed between the lateral fixed raceway surface 164 and the lateral movable raceway surface 165. In this embodiment, each of the lateral fixed raceway surface 164 and the lateral movable raceway surface 165 is an elongated curved surface (inner surface of a groove) that is concave in the direction approaching the other. In this embodiment, each of the multiple rolling elements included in the lateral rolling element row 163 is a metallic sphere (bearing ball).

[0024] In this embodiment, two side spacers 166 are included between the rolling elements that make up the side-side rolling element row 163. These two side spacers 166 regulate the gap between the side-side fixed raceway surface 164 and the side-side movable raceway surface 165 to a predetermined distance, allowing the multiple rolling elements included in the side-side rolling element row 163 to roll appropriately. Furthermore, each of the multiple rolling elements included in the side-side rolling element row 163 is rotatably held by a plate-shaped side cage 167 that is disposed between the side-side fixed rail 161 and the side-side movable rail 162. The two side spacers 166 included in the side-side rolling element row 163 are fixed to the side cage 167. By being held by the side cage 167, each of the multiple rolling elements rolls while maintaining their relative positions to one another.

[0025] In the side guide mechanism 160 configured in this manner, the side fixed rail 161 is fixed to the inside of the fixed wall portion 122 of the fixed member 120. The side movable rail 162 is fixed to the outside of the movable wall portion 132 of the movable member 130. The side movable rail 162 moves in the forward and backward directions together with the movable member 130 relative to the side fixed rail 161 attached to the fixed member 120.

[0026] When the movable member 130 moves relative to the fixed member 120, the two side-side rolling element rows 163 move in the forward / backward direction relative to the side-side fixed rail 161 and the side-side movable rail 162 while remaining held by the side-side retainer 167. The side-side fixed rail 161 and the side-side movable rail 162 each have an engagement member that abuts against the side-side retainer 167. This prevents the two side-side rolling element rows 163 and the side-side retainer 167 from falling off the side-side fixed rail 161 and the side-side movable rail 162. Specifically, as shown in FIG. 3 , a side-side first fixed engagement member 168 and a side-side second fixed engagement member 169 are fixed to both ends of the side-side fixed rail 161 in the forward / backward direction, respectively. A side-side first movable engagement member 170 and a side-side second movable engagement member 171 are fixed to both ends of the side-side movable rail 162 in the forward / backward direction, respectively. The first side movable engagement body 170 engages with the side retainer 167, thereby moving the side retainer 167 and the side rolling element row 163 together with the side movable rail 162 in the advance direction. As described above, when the movable member 130 moves in the advance direction and stops at the arrangement position, the position of the side rolling element row 163 relative to the side fixed rail 161 is determined. The second movable engagement body 171 engages with the side retainer 167, thereby moving the side retainer 167 and the side rolling element row 163 together with the side movable rail 162 in the retreat direction. The first side fixed engagement body 168 and the second side fixed engagement body 169 engage with the side retainer 167, stopping the movement of the side retainer 167. As a result, when the lateral movable rail 162 moves in the forward direction and the lateral first movable engagement body 170 engages with the lateral first fixed engagement body 168 via the lateral retainer 167, the movement of the lateral movable rail 162 is restricted. Also, when the lateral movable rail 162 moves in the backward direction and the second movable engagement body 171 engages with the lateral second fixed engagement body 169 via the lateral retainer 167, the movement of the lateral movable rail 162 is restricted.

[0027] As shown in FIG. 4, the upper guide mechanism 140 includes an upper fixed rail 141, an upper movable rail 142 slidably attached to the upper fixed rail 141, and a plurality of upper rolling element rows 143. The upper rolling element row 143 is composed of a plurality of rolling elements lined up in the movement direction (advance / retreat direction) of the upper movable rail 142 relative to the upper fixed rail 141. The upper rolling element row 143 is disposed between an upper fixed track surface 144 of the upper fixed rail 141 and an upper movable track surface 145 of the upper movable rail 142. In this embodiment, as shown in FIG. 4, the upper fixed rail 141 has four upper fixed track surfaces 144, and the upper movable rail 142 has four upper movable track surfaces 145. Each of these eight track surfaces is formed by a portion of the flat portion of the upper fixed rail 141 or the upper movable rail 142. The upper fixed rail 141 and the upper movable rail 142 are combined so that each of the four upper movable track surfaces 145 faces an upper fixed track surface 144. In other words, the upper guide mechanism 140 has four pairs of opposing upper fixed track surfaces 144 and upper movable track surfaces 145. In each of the four pairs of upper fixed track surfaces 144 and upper movable track surfaces 145, an upper rolling element row 143 is arranged between the upper fixed track surface 144 and the upper movable track surface 145. In this way, the upper guide mechanism 140 has four upper rolling element rows 143.

[0028] In this embodiment, each of the two upper rolling element rows 143 arranged below the upper movable rail 142 includes two upper spacers 146. These four upper spacers 146 regulate the separation distance between the upper fixed raceway surface 144 and the upper movable raceway surface 145 to a predetermined distance, allowing the multiple rolling elements included in the upper rolling element row 143 to roll appropriately. Furthermore, the multiple rolling elements included in the upper rolling element row 143 are rotatably held by a plate-shaped upper cage 147, similar to the rolling elements themselves. The two upper spacers 146 included in the upper rolling element row 143 are fixed to the upper cage 147. By being held by the upper cage 147, each of the multiple rolling elements rolls while maintaining their relative positions to one another.

[0029] In the upper guide mechanism 140 configured in this manner, the upper fixed rail 141 is fixed to the underside of the fixed top plate portion 121 of the fixed member 120. The upper movable rail 142 is fixed to the upper surface of the movable top plate portion 131 of the movable member 130. The upper movable rail 142 moves in the forward and backward directions together with the movable member 130 relative to the upper fixed rail 141 attached to the fixed member 120.

[0030] When the movable member 130 moves relative to the fixed member 120, the two upper rolling element rows 143, like the lateral rolling element rows 163, move in the forward / backward direction relative to the upper fixed rail 141 and the upper movable rail 142 while remaining held by the upper retainer 147. An engagement body that abuts against the upper retainer 147 is disposed on each of the upper fixed rail 141 and the upper movable rail 142. This prevents the two upper rolling element rows 143 and the upper retainer 147 from falling off the upper fixed rail 141 and the upper movable rail 142. Specifically, as shown in FIG. 4 , an upper first fixed engagement body 148 and an upper second fixed engagement body 149 are fixed to both ends of the upper fixed rail 141 in the forward / backward direction, respectively. An upper first movable engagement body 150 and an upper second movable engagement body 151 are fixed to both ends of the upper movable rail 142 in the forward / backward direction. The upper first movable engagement body 150 engages with the upper retainer 147, thereby moving the upper retainer 147 and the upper rolling element row 143 together with the upper movable rail 142 in the forward direction. As described above, when the movable member 130 moves in the forward direction and stops at the arrangement position, the position of the upper rolling element row 143 relative to the upper fixed rail 141 is determined. The upper second movable engagement body 151 engages with the upper retainer 147, thereby moving the upper retainer 147 and the upper rolling element row 143 together with the upper movable rail 142 in the backward direction. The upper first fixed engagement body 148 and the upper second fixed engagement body 149 engage with the upper retainer 147, stopping the movement of the upper retainer 147. As a result, when the upper movable rail 142 moves in the forward direction and the upper first movable engagement body 150 engages with the upper first fixed engagement body 148 via the upper retainer 147, the movement of the upper movable rail 142 is restricted. Also, when the upper movable rail 142 moves in the backward direction and the upper second movable engagement body 151 engages with the upper second fixed engagement body 149 via the upper retainer 147, the movement of the upper movable rail 142 is restricted.

[0031] In this embodiment, in the upper rolling element row 143 and the side rolling element row 163, the rolling elements are inserted between the raceways with a negative clearance. This applies a preload to the rolling elements. This preload minimizes misalignment of the rolling elements and cage due to slippage relative to the raceways. As a result, as the movable rail moves relative to the fixed rail, the rolling elements and cage also move along with the movable rail, but the relative positions of the rolling elements and cage with respect to each raceway surface at that time are uniquely determined.

[0032] 5 is a block diagram showing the functional configuration of the movement control device 190. The movement control device 190 is equipped with a processor and is a device called an ECU (Electronic Control Unit) or the like that controls the movement device 125. The movement control device 190 is equipped with a reference position determination unit 191, an addition unit 192, and a placement control unit 193 as processing units realized by causing the processor to execute a program.

[0033] The reference position determination unit 191 determines a reference position, which is a position that serves as a reference for advancing and positioning the movable member 130 relative to the fixed member 120. The reference position is not particularly limited and may be, for example, a predetermined value. The reference position may also be set to a position of the driver's choice, for example. Furthermore, in cases where multiple drivers with different physiques use the same vehicle, the reference position determination unit 191 may select one from multiple different reference positions. In this embodiment, the reference position determination unit 191 acquires the reference position from the storage device 101.

[0034] When advancing the movable member 130 to the position determined by the reference position determination unit 191, the adder 192 adds an additional value different from that used when the movable member 130 was advanced previously to the reference position determined by the reference position determination unit 191 within a range from a predetermined lower limit distance to a predetermined upper limit distance, thereby deriving the position of the movable member 130. In this embodiment, the additional value added by the adder 192 is a value that changes each time the movable member 130 is advanced. As shown in FIG. 6 , the variation range of the additional value, that is, the range from the lower limit value to the upper limit value that the additional value can adopt, is preferably 5 mm or less. It has been found that if the variation range of the additional value is within 5 mm, the driver can accept it without feeling uncomfortable even if the position of the movable member 130 changes each time from the reference value set by the driver. Specifically, the adder 192 limits the additional value so that the deviation from the reference position is between −2.5 mm and +2.5 mm.

[0035] The method by which the adder 192 adopts an additional value different from the value used the previous time the movable member 130 advanced is not particularly limited. For example, the adder 192 may add a predetermined reference value to the additional value each time the movable member 130 advances, and reset the additional value to the lower limit value when the upper limit value is reached. Alternatively, the adder 192 may randomly generate an additional value that is a multiple of the predetermined reference value between the lower limit value and the upper limit value. The reference value used by the adder 192 to determine the additional value is preferably 10% or less of the diameter of the rolling elements included in the upper rolling element array 143 and the side rolling element array 163. The reference value is selected from a range equal to or greater than the minimum distance (e.g., 0.1 mm) over which the placement control unit 193 can control the movement of the movable member 130. When the diameters of the rolling elements included in the upper rolling element array 143 and the side rolling element array 163 differ, the reference value may be determined based on the smallest diameter, or may be determined by statistically processing the different diameters.

[0036] The placement control unit 193 controls the moving device 125 so that the movable member 130 is positioned at the placement position calculated by the adder 192. For example, if the motor included in the moving device 125 is a servo motor, the moving device 125 is a device that can move the movable member a minimum distance in the retracting direction by rotating the motor a minimum angle (e.g., one pulse). In the case of such a moving device 125, the placement control unit 193 outputs to the moving device 125 a number of pulses corresponding to the placement position. Note that the minimum distance over which the moving device 125 moves the movable member 130 is not limited, but can be, for example, in the range of 0.05 mm to 0.5 mm. The placement control unit 193 may also update the origin position of the movable member 130 based on a signal from a sensor that acquires the origin position of the movable member 130.

[0037] According to the steering device 100 relating to the embodiment described above, the movable member 130 is not always positioned at a predetermined reference position, but is positioned at a different position each time the movable member 130 advances. This makes it possible to change the position of the load applied to the lateral guide mechanism 160 and the upper guide mechanism 140, which are guide mechanisms, and to level out wear on the upper fixed track surface 144, the upper movable track surface 145, the lateral fixed track surface 164, and the lateral movable track surface 165, thereby suppressing localized wear. Therefore, it is possible to suppress rattle over time of the operating member 210 attached to the movable member 130 and rattle due to localized wear when the movable member 130 advances or retreats.

[0038] Furthermore, by limiting the deviation of the position of the movable member 130 from the reference position to within 5 mm, it is possible to suppress any discomfort felt by the driver.

[0039] Furthermore, if the guide mechanism uses rolling elements, the reference value used to determine the additional value can be set to 10% or less of the diameter of the rolling elements, thereby smoothly leveling out wear on the raceway surface. This makes it possible to suppress rattling of the movable member 130 even if a rolling element passes through a worn area.

[0040] The present invention is not limited to the above-described embodiments. For example, the present invention may be embodied in another embodiment by arbitrarily combining the components described in this specification or by excluding some of the components. Furthermore, the present invention also includes various modifications that would occur to a person skilled in the art without departing from the spirit of the present invention, i.e., the meaning of the wording of the claims.

[0041] For example, the movement control device 190 may include a history acquisition unit 196 that acquires a position history, which is a history regarding the placement position of the movable member 130, and the addition unit 192 may determine an addition value from the position history so as to place the movable member 130 in a position with a low placement rate. The placement rate may be the frequency with which the movable member 130 was placed in a specific placement position, or may be a value indicating the accumulated time that the movable member 130 was placed in a specific placement position. Specifically, the movement control device 190 may include a timing unit 194, a recording unit 195, and a history acquisition unit 196, as shown in FIG. 7.

[0042] The timer 194 measures the time from when the movable member 130 advances and reaches the arrangement position to when it moves out of the arrangement position.

[0043] The recording unit 195 adds the time measured by the timing unit 194 to the cumulative time associated with the placement position where the object was previously placed at the same position, and stores the result in the storage device 101.

[0044] The history acquisition unit 196 acquires the placement rate as a position history based on each placement position corresponding to the reference position determined by the reference position determination unit 191. The addition unit 192 determines an addition value so as to place the movable member 130 at a position with a low placement rate, which is the ratio of the time that the movable member 130 was located at each placement position corresponding to the reference position to the total time that the movable member 130 was located at each placement position. The addition unit 192 adds the determined addition value to the reference position to derive the placement position.

[0045] The placement control unit 193 places the movable member 130 at the placement position calculated by the adding unit 192, thereby leveling out the time spent at the placement position corresponding to the reference position. Therefore, it is possible to level out the wear of the upper fixed track surface 144, the upper movable track surface 145, the lateral fixed track surface 164, and the lateral movable track surface 165, which are guide mechanisms, with higher accuracy than by leveling out the number of times the movable member 130 is placed at the placement position.

[0046] In addition, when the position where the advancement of the movable member 130 is restricted by the engaging body of the guide mechanism is the reference position, the adding unit 192 may change the upper limit value and the lower limit value based on the reference position, such as by setting the upper limit value to 0 mm and the lower limit value to -5 mm.

[0047] Furthermore, the steering device 100 has been described as being mounted on a vehicle capable of automatic driving and moving the operating member 210 to the front of the vehicle where the driver cannot operate it during automatic driving, but the steering device 100 may also be mounted on a vehicle that does not have an automatic driving function.

[0048] Furthermore, the number of rolling element rows that each of the lateral guide mechanism 160 and the upper guide mechanism 140 has may be one or more. In other words, as long as the lateral guide mechanism 160 has at least one lateral rolling element row 163, it can slide the lateral movable rail 162 relative to the lateral fixed rail 161. Similarly, as long as the upper guide mechanism 140 has at least one upper rolling element row 143, it can slide the upper movable rail 142 relative to the upper fixed rail 141. For example, the upper guide mechanism 140 may have only one upper rolling element row 143 between the inner surface of the upper fixed rail 141 and the upper surface of the upper movable rail 142. In other words, the number of upper rolling element rows 143 in the upper guide mechanism 140 may be three. In this case, it is preferable to position the upper rolling element row 143 arranged along the upper surface of the upper movable rail 142 in the center of the upper fixed rail 141 and the upper movable rail 142 in the X-axis direction, from the perspective of achieving stable sliding movement of the upper movable rail 142.

[0049] In the lateral guide mechanism 160, the number of contact points between the rolling elements and the track surface may be two, the same as in the upper guide mechanism 140. For example, a rail mechanism having the same structure as the upper guide mechanism 140 may be disposed at the position of the lateral guide mechanism 160 with its thickness direction (the direction in which the fixed rail and the movable rail are aligned) facing the width direction of the vehicle (the X-axis direction). In this case, in the rail mechanism, the movable rail is structurally allowed to move (displace) in the vertical direction of the vehicle. However, like the upper guide mechanism 140, the rail mechanism can resist external forces in the vertical direction of the vehicle, and therefore the movement of the movable member 130 in the vertical direction of the vehicle is primarily restricted by the rail mechanism.

[0050] The rolling elements may be of a type other than ball bearings. For example, roller bearings may be used as the rolling elements and / or the rolling elements. The materials forming the rolling elements and / or the rolling elements are not limited to metal. For example, the rolling elements and / or the rolling elements may be formed from resin.

[0051] The rail mechanisms provided in the steering device 100 do not have to be limited to the lateral guide mechanism 160 and the upper guide mechanism 140 .

[0052] The steering device 100 may further include a tilt mechanism that changes the tilt in the up-down direction of the steering device 100. The tilt mechanism changes the tilt in the up-down direction of the fixed member 120, for example. This allows the up-down position of the operating member 210 to be adjusted according to the driver's intention.

[0053] The moving device 125 may drive the movement of the movable member 130 by a method other than a feed screw method. For example, the moving device 125 may drive the movement of the movable member 130 in the forward and backward directions by extension and contraction or forward and backward movement of a rod body fixed to the movable member 130. [Industrial Applicability]

[0054] The present invention is useful as a steering device that can move an operating member, and can be used in vehicles equipped with wheels or caterpillar surfaces, such as passenger cars, buses, trucks, agricultural machinery, and construction machinery. [Explanation of symbols]

[0055] 100...Steering device, 101...Storage device, 110...Input shaft body, 120...Fixed member, 121...Fixed top plate portion, 122...Fixed wall portion, 125...Moving device, 126...Fixed bracket, 127...Screw, 128...Rotation drive device, 130...Moveable member, 131...Moveable top plate portion, 132...Moveable wall portion, 135...Through hole, 138...Moveable nut, 140...Upper guide mechanism, 141...Upper fixed rail, 142...Upper movable rail, 143...Upper rolling body row, 144...Upper fixed raceway surface, 145...Upper movable raceway surface, 146...Upper spacer, 147...Upper retainer, 148...Upper first fixed engagement body, 149...Upper second fixed engagement body, 150...Upper first movable engagement body, 151...Upper second movable engagement body , 160...Side guide mechanism, 161...Side fixed rail, 162...Side movable rail, 163...Side rolling body row, 164...Side fixed track surface, 165...Side movable track surface, 166...Side spacer, 167...Side retainer, 168...Side first fixed engagement body, 169...Side second fixed engagement body, 170...Side first movable engagement body, 171...Second movable engagement body, 190...Movement control device, 191...Reference position determination unit, 192...Adding unit, 193...Layout control unit, 194...Timekeeping unit, 195...Recording unit, 196...History acquisition unit, 200...Steering system, 210...Operating member, 220...Steered wheel, 230...Steering mechanism unit, 231...Rack shaft, 232...Tie rod, 233...Steering actuator

Claims

1. A steering device used for steering a vehicle, a fixing member fixed to the vehicle; a movable member that rotatably supports an operating member and is movable relative to the fixed member; a guide mechanism that guides movement of the movable member relative to the fixed member; a moving device that moves the movable member relative to the fixed member; a movement control device that controls the movement device, The movement control device includes: a reference position determination unit that determines a reference position at which the movable member is to be disposed; an adder that, when advancing the movable member, adds an additional value different from that used when the movable member was previously advanced to the reference position within a range from a predetermined lower limit distance to a predetermined upper limit distance to derive a placement position; a placement control unit that controls the moving device so that the movable member is positioned at the placement position calculated by the adding unit. Steering device.

2. The range from the lower limit to the upper limit of the added value is 5 mm or less. The steering device according to claim 1 .

3. The guide mechanism includes: a fixed rail fixed to the fixed member; a movable rail fixed to the movable member; a rolling element disposed between the fixed rail and the movable rail; a cage that holds the rolling elements; a movable engaging body fixed to the movable rail and engaging with the retainer; 3. A steering device according to claim 1 or 2.

4. the additional value to be added to the reference position is a multiple of a predetermined reference value, The reference value is selected from a range of 10% or less of the diameter of the rolling element and the minimum distance that can be controlled by the placement control unit. The steering device according to claim 3.

5. The movement control device includes: a history acquisition unit that acquires a position history that is a history regarding the arrangement position of the movable member; The adding unit From the position history, an additional value is determined so that the movable member is placed at a position with a low placement rate. A steering device according to any one of claims 1 to 4.

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